I change mine every fall which usually coincides with about 7K miles.

 

My indy mechanic recommends every 5K miles, whenever that occurs. I choose to go with every 6 months instead, which works out to about 6K miles.

 

Every spring I take it in for it's yearly service. Usually I will have driven between 3-4000 miles.

I'm going to start oil testing next year and do the oil filter exam. Meant to start this year, but I forgot to get an oil sample when the service was done.

 

7.5K/annually

 

Bad idea for two reasons. If you let the car idle for only a few minutes you will build up water in your oil. Same with short trips. Long runs are needed to heat the oil enough, and for long enough, to purge the water. Short trips and idling for a short period will cause a build up of water and that water will condense in the engine in the cold months.

Open your oil filler cap after a long drive and you will see some steam coming out, and maybe some milky stuff in the filler neck. That will give you an idea of the water in the oil.

The other thing is that after a long drive oil will have been as widely distributed to as much of the engine as possible. Once the car is shut down a thin film of oil will be left behind which will protect the metal from corrosion. Running the engine and idling for a short time will remove that film and not be long enough to lay down a new film everywhere.

 

Change oil on your birthday or 5000 miles whichever come first.

 

I appreciate all the replies. Thanks! I put on 8000 miles since I got my car last Feb, so it will definitely be the mileage that is my deciding factor, and not time.

Thanks again gentlemen!

 

Sounds like a text book reply. With all due respect, you got some of it right, but you are still not 100% clear on what actually is going on.

I admit, it's best to take a long drive every week and let the car reach full operating temperature, and keep it there for several miles so all the moisture burns out of the oil. This in reality could take a long time, hours even.

Short trips and short running cycles do not necessarily add water to the oil in and of itself. Where water is a byproduct of combustion, the water doesn't enter the oil as a result of running. It enters thru the valves that are left open to the atmosphere when the motor is not running. Inside a motor is mainly air spaces, and the air naturally contains moisture. Condensation naturally occurs with temperature changes and as it cools down at night droplets form on areas above and end up falling eventually into the oil sump. Being heavier than oil the water collects at the lowest point. This cycle continues daily with temperture fluxuations when a car sits.

The oil that coated all internal parts while the motor was running starts migrating to the lowest part of the motor as soon as the ignition is turned off. After sitting for several days, the oil film becomes virtually non existant and can no longer protect critical parts from corrosion and oxidation. Different chemical compounds in the oil itself and all the internal motor components in the presence of moisture added with combustion byproducts produce acids. So now we have acidic moisture droplets forming and dripping on critical components that have sloughed off their protective oil film. This is where major wear begins inside a motor. Not from running, but when sitting for days, stored, all the while the owner is clueless at to what's really going on.

You can interrupt the cycle by starting the motor. Even after a few seconds of running, oil will reach and coat every moving part. Longer is better, but just a few minutes is much better than nothing. While you're at it if you move the car just a few feet, you will coat all the wheel bearing ***** with a fresh coat of grease a work the clutch and brake components.

 

C'mon you guys, it's both a dessert topping AND a floor wax!

The 1 year recommendation is just a guideline. Can't really know without a used oil analysis. FWIW, I've had a few UOAs on my cars (P cars and others marques) with a number of different oils and NONE of them lasted more than 10,000 miles/1 year. Sometimes the oil doesn't even last 5,000 miles. Sometimes the total acid number (TAN) and total base number (TBN) indicate the acid fighting ability of the oil is depleted. This happens even if the water content of the oil is within acceptable spec. I've never had a car with low mileage and extended time interval, that would be an interesting UOA to see.

Irregardless (is that even a word?) of oil, if idling my car for a short time I like to make sure the exhaust system gets up to temp. I don't want the combustion water condensing and rusting it out prematurely.

 

I wanna say one more thing......changing your oil often and not getting too ridiculous, though expensive, will only do good for your motor. Changing your oil at longer intervals, will only, if it does anything at all, will let you motor wear a little more quickly, but definitely will not do any good for your motor, I think all of you would agree.

 

Same logic as toilet seat covers

 

Happy friday! Irregardless is not a word. And i agree that 10k is too long for even the most high tech synthetic engine oil.

 

Ah, but the problem with that logic is that if you want to do the best for your car, you'd change it every week.

It's all a compromise...

 

...

 

Every weekend for me.